These Affordable Earphones Are Made Using An Advanced 3D Printer

The shells of the Brainwavz Koel earpieces are made by an advanced 3D resin printer for a really comfortable design and fit.

Brainwavz

These days, In-Ear Monitors – or IEMs for short – are landing on my desk with increasing frequency. IEMs are earbuds that fit deep into the ear canal, and are often driven by a device called a balanced armature. These miniature speakers are different from the regular dynamic drivers used in most earbuds and headphones. These tiny devices are capable of incredible precision and have traditionally been used in hearing aids. They once were very expensive to produce, but now mass production in China means balanced armatures are finding their way into budget and mid-price earphones.

One of the latest IEMs to arrive for review is Koel from Brainwavz Audio. Koel IEMs are, according to Brainwavz: “Tuned to produce a balanced and accurate sound signature, with little to no coloring, presenting a truly genuine audio experience and a great introduction to the world of refined audio”.

Well, that’s actually quite an accurate summary of what Koel IEMs can do. These midrange earphones remind me very much of Shure’s excellent SE Noise Isolating earphones, both in appearance and sound, but at half the price. The Koel IEMs are lightweight and have an excellent ergonomic fit that sits comfortably in the ear once they’re in position and I soon forgot I was wearing them. The design is the 'over-the-ear' type, which means the cable fits over the top of the ear, using hooks of reinforced cable, and then the earpieces fit deep into the ear canal. This fit provides a secure and relatively comfortable positioning, although they can be a bit of a nuisance to take off if you need to listen to someone who has decided they really must talk to you while you’re enjoying music.

The Koel earphones use a balanced armature driver which is able to deliver really precise sound.

Brainwavz

The unique see-thru shell earpieces that house the balanced-armature drivers look a little homemade with their mottled finish, but that’s because they are manufactured using a state-of-the-art 3D resin printer. According to Brainwavz, this method of 3D printing enables the production of an ear-shell shape that’s not possible by conventional production methods. The rest of the Koel IEMs is assembled from components that Brainwavz has sourced from USA and Europe.

The Koel IEMs are provided with a specially coated cable that’s terminated in two detachable MMCX connectors at the earpiece end and a 3.5mm stereo jack at the other end. The inclusion of MMCX connectors means it’s so easy to replace the cable should it ever become damaged. It’s even possible to source a longer compatible cable or one that includes a remote control and a microphone. The cable is coated in a special plastic that has a slightly rough texture that is brilliant for not tangling. The cable is also excellent at not transmitting microphonics, those annoying vibrations that you get with some earphones when their cable chafes on a zip, clothing or another part of the cable.

Included in the Koel package are six sets of high-quality silicone ear tips in different sizes. There’s also a set of the excellent Comply T-100 memory foam tips that adapts to the shape of the ear canal using the heat of the body to mold precisely. The Comply tips provide really good noise isolation and are great for lengthy listening sessions. Finally, there’s a stylish carrying case is included to protect the earphones when they’re not in use. I really wish more manufacturers would provide a case to protect their earphones.

The Koel IEMs use detachable connectors which means the cable can easily be replaced by any other cable conforming to the MMCX standard.

Brainwavz

And so to the most important part of the review: how do the Brainwavz Koel sound. At first, I was doubtful that these affordable IEMs would be able to produce enough bass. IEMs using just a single balanced-armature driver deliver great treble but they are notorious for producing a really lightweight bass. Well, I’m pleased to say that the Keol have been carefully tuned to produce a bass that’s beautifully articulated without ever being overblown or flabby. The treble is, as I expected, delivered with laser-guided precision and can reproduce cymbals and top-guitar notes superbly. There is so much detail in the sound but it never becomes harsh or fatiguing. If you like really tub-thumping bass levels then you may not like the Koel as they are refined and incredibly accurate compared with cheaper earphones tuned to over-deliver bass.

Verdict: These are probably the best and most uncolored single balanced-armature earphones I’ve ever tried at this price level. The Brainwavz Koel have great tonal accuracy, musical rhythm, as well as a truly toe-tapping bass without any coloration. I would say they are worthy of the IEM title and are a great introduction to what is possible if you spend just a little more on a pair of earphones. The build quality is exceptionally durable, and if this is what 3D resin printing is capable of, I can’t wait for Brainwavz to start offering custom printed IEMs. I don’t know if they’re planning to offer such a service, but I’d be first in the queue to try a pair.